A delighted Sir Alex Ferguson hailed Robin van Persie after Manchester United clinched the Premier League title on Monday - and believes consistency was a huge factor throughout the campaign.

A hat-trick from Van Persie in a 3-0 win against Aston Villa at Old Trafford sealed the championship with four games to spare, with United clinching their 20th league crown.

"You can go on and on about losing the title [last season]… At the end of the day, our consistency for the last 20 years has been unbelievable," Ferguson told Sky Sports after the match. "It's amazing, 13th championship in the Premier League. I think we deserved it. Our consistency has won us the league. Fantastic performance from our players tonight."

He added: "I think the focus of the team was good. The focus on the challenge from [Manchester] City, we came up trumps with it.

"Nostalgia plays tricks in people's minds. The amount of times you've said 'when I was a boy, things weren't the same'. It's nostalgia. Put it in context, we've got 84 points from 34 games, we've never done that.

And Ferguson praised Van Persie for the impact he has made since his move to Old Trafford from Arsenal last summer. "He has been unbelievable. His form in the first six months was fantastic. He had that spell where he had not scored a goal. Like every striker, he had a dry spell."

Villa manager Paul Lambert credited his players for the way they did not let their heads drop after conceding the early goals, and praised United for their triumph.

"I knew it was going to be really, really tough. But we kept on going and it was important we did not capitulate like we did at Stamford Bridge earlier this season, but congratulations to Manchester United," Lambert said, whose side are three points above the relegation zone.

"I am proud that my lads kept on going, credit to them, especially against the best team in the country.

"You want to give a good account of yourselves at Old Trafford but after the start we had you are not wanting to concede more goals. The lads kept on going and, for us, next Monday [against Sunderland] is the one we have to win.

"Manchester United have worked really hard for each other, they have a winning mentality and the best team always wins the league."